1. Field of the Invention
This invention relates to a personal identification system, and to a corresponding method of personal identification.
2. Brief Description of the Background of the Invention Including Prior Art
There are many occasions on which a person's identity needs to be reliably confirmed to someone to whom they are not known. Thus members of the armed forces, and civilians having access to security areas, are often required to carry security cards, and to have their fingerprints recorded. Persons requesting personal credit are often issued with a credit card containing a numerical code, or with a picture of the authorised user securely affixed to the card. A cheque guarantee card will usually have recorded thereon the authorised user's signature, which can be electronically compared (by a computer based system) with a signature written on a cheque.
The disadvantages of relying solely upon a security card or pass (including cheque guarantee cards) or upon a standard credit card have long been recognised; photographs can be replaced, signatures can be forged, the card or pass can be stolen, a password or other identifier can inadvertently be revealed.
There has therefore been proposed a personal identification system comprising a card and a machine-reader, the card having both a first area with a permanent record of a singularity individual to the authorised user of the card and a designated card and a machine-reader, the card having a first area with a permanent record of a singularity individual to the authorised user of the card characterised by a designated second area adapted temporarily to record that singularity, the permanent and temporary records being in a form permitting direct comparison by the machine-reader.
We also propose a personal identification system comprising a card having a first area with a permanent record of a singularlity individual to the authorised user of the card characterised by a designated second area of the card adapted temporarily to record that singularity, the permanent and temporary records being at positions on the card and in a form permitting direct comparison. Preferably the card will be machine-readable, for an automatic and direct comparison of the permanent and temporary records, and in such case the permanent and temporary records need not be in visible form, so that if the card is stolen, the thief may not know which singularity to seek to counterfeit.
We further propose a method of personal identification characterised by issuing a card having a permanent record of a singularity peculiar to a person authorised to use the card, requiring the person to provide a temporary record of that singularity each time the card is used, machine-reading the permanent and temporary records, and obtaining a match or non-match indication from the machine-reader. second area adapted temporarily to record that singularity, the permanent and temporary records being in a form permitting direct comparison by the machine-reader.
One personal identification system of this type is disclosed in U.S. Pat. No. 4,582,985 and in British Patent Application 2185937A. The credit or similar card incorporates a computer-produced image of a thumb or fingerprint of the authorised holder, and includes also a fingerprint reader, a processor for print matching and an indicator such as a liquid crystal display. When a transaction is to be verified, a finger or thumb is applied to the reader, operating a pressure sensitive switch which causes the print to be compared with that held in the card. If there is a satisfactory match this causes for instance the holder's account number or personal identification number to be displayed on the indicator on the card.
A disadvantage of the personal identification system described in the preceding paragraph is that a reliable reader capable of accurately distinguishing between fingerprints cannot easily be located within the thickness of a card. Another disadvantage is that the card carries its own indicator, which is a help to anyone intending to use the card fraudulently in their (private) experiments to achieve a suitable counterfeit fingerprint.
Another personal identification system has been proposed using however a machine-reader or processor separate from the card.
Such an arrangement is disclosed in U.S. Pat. No. 3,383,657; the second designated area is on the machine-reader. Although avoiding the disadvantages mentioned in the preceding paragraph, a determined third party can still defeat a security check, as by using an impression of the authorised user's fingerprint.